(a) Field of the Invention
This invention relates to 5-(pyridinyl)pyridin-2-amines, useful as cardiotonics.
(b) Description of the Prior Art
Lesher and Gruett British Pat. No. 1,322,318, published July 4, 1973, shows as intermediates for preparing antibacterially active 1-alkyl-1,4-dihydro-4-oxo-7-PY-1,8-naphthyridine-3-carboxylic acids and esters (where PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents) 2-amino-6-(4- or 3-pyridinyl)pyridine, alternatively named 6-(4- or 3-pyridinyl)pyridin-2-amines.
D. A. Inoyatova et al. [Chem. Absts. 74, 125,360b (1971); Tr. Samarkand. Gos. Univ. 1969, No. 167, 173-4 (Russ.) From Ref. Zh., Khim 1970, Abstr. No. 5Zh482] report the amination of 3,3'-bipyridine and subsequent thin-layer chromatography using diethyl ether to produce 6-amino-3,3'-bipyridine, alternatively named 5-(3-pyridinyl)pyridin-2-amine.